ORTHOPTERA. 
309 
Order III. ORTHOPTERA. Plates XXV-XXXVIII. 
Blattarle. 
THE HEAD. 
Blatta americana 9 . The head is held vertically. The epicranium is 
broad and smooth; the ocelli are absent or obsolete. The clypeus is 
broad and short, no suture separating it from the epicranium. The 
gen® are large, a genal ridge separating the gen® from the orbits. 
The gula is broad and short. 
THE thorax. (Plate XXVI.) 
Notum. 
The pronotum (PI. XXVIII) is broad and flat, as long as broad. 
The mesonotum (PI. XXX) is remarkably broad and flat, two-thirds as 
long as broad. The pr®scutum is wanting (unless represented by a 
transverse strip in front 1 ?). The scutum is flat, consisting of two square 
sclerites separated slightly by the rudimentary scutellum, which latter 
is lanceolate, narrow, triangular, and divided into two portions, i. e., the 
posterior or scutellum proper, which is subquadrate, broader than long, 
and a narrow, long continuation which reaches to the front edge of the 
scutum, between its two sclerites. 
The postscutelluin is represented by a well-marked transverse band 
behind the scutellum, but not separated from the scutellum by a well- 
marked suture. 
The metanotnm (PI. XXX) is like the mesonotum, but with no traces 
of apr®soutum; while the scutellum is much more distinct, diamond- 
shaped, with distinct sutures, the acute apex not quite reaching the 
front edge of the scutum ; behind clearly demarked from the postscu- 
tellum, which forms a definite transverse band. 
Pleurum. 
The pleurites are very hard to make out, owing to the flatness of the 
body. 
Propleurum. (PI. XXIX). The episternum is divided into three 
pieces, the anterior a ridge extending from the sternum to the roof of 
the scutum; the hinder two a lower piece resting on the trochantiue, 
and an upper, larger and completely chitinous piece exteuded to the 
suture. The eirimerum is a very irregular, oblong regioii, partly mem- 
branous. 
Mesopleurum. (PI. XXXI.) The episternum in this arthromere is also 
subdivided into three pieces: the anterior (1) broad and resting on the 
sternum and reaching around totheepimeruin; and (2) a narrow, lance- 
olate-oval piece not visible from the side; the third sclerite (3) is a broad, 
triangular piece (which may be the epimerum, but is probably not). A 
